SBT test extremely slow on macOS Sierra

I seem to have a problem with performance of "sbt test" after upgrading to macOS Sierra. On a previous version of OS X it took about 40-50 seconds to finish. macOS Sierra times are much higher than that. Last run I did was around 15 minutes. Compile times are about the same as on 'El Capitan'.

I'm the only one from my team to try this new macOS so I can't tell if it's only happening on my mac or is it a universal issue.

On the post I also link to a github project to help troubleshooting the issue and validating the solution.

The problem is related (I believe) on how the localhost name resolution works and how the java.net.InetAddr class is retrieving the addresses. I verified with few colleagues and apparently it doesn't happen to everyone who upgraded to Sierra, but I'm still investigating the roots of this change.

The solution anyway was the same that antid0te implemented and worked immediately.